This invention relates generally to a magnetically actuated valve system and more specifically to a magnetically actuated valve system in which at least two solenoid valves are actuated by a single electromagnetic actuator.
In typical electromagnetically actuated propellant valves used in bi-propellant systems, a first propellant (fuel) flows through an upstream valve to a downstream valve such that the first propellant will be directed into contact with a second propellant (oxidizer) flowing through a second upstream valve to a second downstream valve within a thruster portion of an engine or the like, whereby the combined propellant will be ignited. The flow of each of the first and second propellants is simultaneously controlled and maintained in the correct proportions by a single magnetic circuit actuating two magnetically linked valves, each housed in a manifold assembly.
U.S. Pat. Nos. 3,443,585, 3,472,277 and 4,223,698 disclose various magnetically actuated valve systems wherein a single electromagnetic excitation will actuate each of two valve members, each of which serves its own pressure-fluid flow. In the xe2x80x2585 patent, a permanent magnet is the common middle element of two separate solenoid-actuated magnetic circuits. Excitation of one solenoid opens both valves; excitation of the other solenoid closes both valves; and the permanent magnet holds the actuated condition of both valves. The xe2x80x2277 and xe2x80x2698 patents each disclose an electromagnetic actuating system wherein a single solenoid coil actuates two magnetically linked valves to open condition, against the preload of springs to load valve members in the valve-closing direction. In all cases, construction is highly specialized and complex, leading to unduly expensive products.
U.S. Pat. No. 5,450,876 discloses an electromagnetically actuated multiple-valve construction within a single welded housing which contains each of two series-connected valves and a single magnetic circuit for concurrently operating an upstream and a downstream valve.
Consequently, there exists a need in the art for a valve system having the functional advantages of the xe2x80x2876 patent without a welded construction, which adds weight. There also exists a need in the art for a magnetically actuated valve system to provide a pair of magnetically operated valves movable between a power applied and a power removed position by a magnetic solenoid actuator assembly for simultaneously controlling and maintaining first and second propellants in the correct proportions through separate manifold assemblies of a single system. There also exists a need in the art to make a magnetically actuated valve system that is simpler, lighter and more cost effective.
To meet the described need, one aspect of the invention provides a magnetically actuated valve system. The magnetically actuated valve system comprises a first conduit and a second conduit. A first sealing structure is moveable in response to a magnetic force to an open position and spring biased toward a closed position. The closed position prevents fluid flow through the first conduit. A second sealing structure is moveable in response to a magnetic force in a second direction, substantially opposite to the first direction, to an open position and biased toward a closed position. The closed position prevents fluid flow through the second conduit. A magnetic actuator assembly is constructed and arranged to actuate the first and second sealing assemblies substantially simultaneously by moving the first and second sealing structures in the first and second directions, respectively.
Other objects, features, and advantages of the present invention will become apparent form the following detailed description, the accompanying drawings, and the appended claims.